ALWAYS
considered
to
be
present.
Division
2
means
the
hazard
is
only
present
under
abnormal
conditions.
The
Group
defines
the
explosiveness
of
the
hazard.
The
Temperature
Code
specifies
the
temperature
at
which
a
hazard
will
ignite.
HEATREX
can
provide
designs
suitable
for
all
of
the
above
conditions,
but
a
heater
should
never
be
placed
in
an
environment
not
noted
on
the
heater
nameplate.
NEVER
operate
the
heater
in
an
atmosphere
with
an
ignition
code
temperature
LOWER
THAN
the
nameplate
rating.
The
user
must
determine
the
actual
area
classification.
Special
design
considerations
for
electric
heaters
used
in
hazardous
locations:
5
1.
Locate
all
electrical
connections
in
an
appropriate
enclosure.
2.
Prevent
surface
temperatures
of
the
heater
from
exceeding
the
design
ignition
temperature.
HEATREX
Pipe
Insert
Heaters
designed
for
hazardous
locations
are
provided
with
an
enclosure
designed
to
contain
an
explosion.
When
the
design
temperature
of
the
process
exceeds
the
rated
ignition
temperature,
it
is
critical
that
the
heater
and
all
customer
piping
is
properly
insulated.
A
hazardous
area
heater
must
be
powered
and
controlled
by
a
heater
control
panel
designed
to
provide
necessary
over
‐
temperature
safety
interlocks.
Contact
HEATREX
if
assistance
is
required
to
properly
control
and
protect
the
heater.
Never
apply
power
to
a
heater
in
a
hazardous
atmosphere
unless
all
terminal
box
covers
are
properly
installed
with
all
cover
bolts.
All
conduits
entering
the
heater
terminal
box
must
be
sealed
within
18”
of
the
heater
using
an
explosion
‐
proof
conduit
seal.
Any
unused
openings
must
be
properly
sealed
with
a
steel
pipe
plug.
Follow
the
NEC
for
specific
conduit
requirements
such
as
the
requirement
for
Rigid
Conduit.
To
ensure
proper
flamepath,
all
threaded
conduits
must
use
rated
fittings
and
be
tight,
with
a
minimum
of
5
good
threads
engaged.
Any
machined
metal
‐
to
‐
metal
surfaces
on
terminal
boxes
must
be
handled
carefully
to
prevent
scratches
which
may
void
the
explosion
‐
proof
rating.
Proper
grounding
of
equipment
in
hazardous
areas
is
critical
to
eliminate
potential
sources
of
sparking.
Replacement
of
electrical
components
should
only
be
done
by
authorized
personnel
familiar
with
the
requirements
of
maintaining
electrical
equipment
in
an
explosion
‐
hazard
area.
WARNING - Risk of Explosion
Operating
the
heater
at
a
voltage
higher
than
the
nameplate
value
may
result
in
elevated
temperatures
and
amperage
above
the
design
ratings
.
HX79
‐
2150
‐
83
‐
1
